Reversible-point excavating tooth



June 25, 1929. A. F. WIKSTROM REVERSIBLE POINT EXCAVATING TOOTH "WW u Filed Sept. 17, 1927 Patented June 25, 1929.

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ADOLF FREDERICK WIKSTROM, OF CHICAGO HEIGHT-El, ILLINOIS, ASS'EGNOR '10 AMERI- CAN MANGANESE STEEL COMPANY, SF CHICAGO,

MAINE.

ILLINOIS, A CORTPORATION 0F REVERSIBLE-POINT EXCAVATENG TGGTH.

Application filed September 1'7, 1927. Serial 1W0, 220,089.

This invention relates to teeth for use on excavating implements, such, for instance, as power opera-ted dippers, buckets, and the like, in which, for consideration of economy, it is usual to produce the tooth in separately formed point and base members in order that the point, one side of which wears away more rapidly than the other, may be reversed in position upon the base of the tooth; and the invention has for its object to provide an improved form of articulation be tween the meeting ends of the separately formed point and base members, and particularly a form of articulation which, while being very secure in its capacity to withstand stresses imposed upon the point when in use, will also be of such. simple design as to make it very economical to produce by foundry practice and from manganese steel or other material which must he finished by grinding rather than machining.

The invention proceeds upon the principles of assembling the point with the base through means of rabbet splicing, and particularly an assembly which involves splicing in both the vertical and horizontal longitudinal plane of the tooth; the rabbets formed in the members, whereby they are permitted to overlap, being such that the point will be received upon the base in either of two positions of revolution, 180 apart,

and thereby present either surface of the point downward or in the direction of greater wear, at will. Stated more specifically or in terms of its preferred embodiment, the invention involves the use, upon each member, of a pair of lugs located on opposite sides of both the vertical and horizontal medial longitudinal planes of the tooth, or on diagonally opposite sides of the longitudinal axis of the tooth, and with vertically and laterally open recesses positioned on the other diagonal of the structure, so that in assembly the recesses of each member re ceive the lugs of the other member and in the lapping of the lugs there is lateral seating of each lug of each member against both lugs of the other member, or, in other words, both vertical and horizontal lateral seating of the lapped lugs; transverse securing bolts being passed through the lapped lugs in a manner to draw them into firm seating in at least one direction; and these bolts being parallel and sufficiently remote from the longitudinal axis of the tooth to develop a turning moment between the members and causing the respective lugs on a member to seat in opposite directions.

In the accompanying drawing, in which the preferred embodiment of the invention is shown by way of illustration Figures 1 and 2 are, respectively, a plan View and a side elevation of the portion of the tooth with which the invention is immediately concerned, and with the point and base members in complete assembly.

Figures 3 and t are pe1.'s ective views showing the point member and a portion of the base member segregated; and

Figure 5 is a section on the-line 5* Figures 1 and 2.

A represents the forward or point-receiv mg portion of the tooth, and B represents theseparately formed point reversibly mounted thereon. In order to adapt these two members for assembly or articulation upon the principles of both vertical and horizontal rabbet splicing, the base is provided with lugs 1, 2 lying mainly on diagonally opposite sides of the longitudinal axis of the complete tooth, or, in other words, on opposite sides of both the vertical and horizontal medial longitudinal planes of the tooth, so that there remain, defined by inner faces of these lugs, spaces t and 5 in similar geometrical positions of the tooth, that is to say, on the other diagonal of the structure or similarly spaced with relation to the two medial longitudinal planes of the tooth; and in order to provide a more substantial foundation or mounting base, the lugs 1, 2, in at least one direction, as shown in dotted lines in Figures 2 and l and better seen in Figure 5, are extended across at least one of the medial longitudinal planes, for instance, the horizontal plane, to bring them into overlap over an area represented generally by the reference character 6, and this area of in tegral overlap between the lugs on one memher better adapts these lugs to resist transverse stresses both in vertical and horizontal directions. And to adapt the point B to enter into assembly with the base A, the point is provided wit-h lugs 7 and 8, so formed as to leave at the side of each lug a recess 9 orlO, said lugs 7 and 8 and recesses 9 and 10 being disposed symmetrically with the lugs and recesses of the base so that in assembly a recess of each member receives a lug of the other member, and the lugs are permitted to overlap and enter into bearing transversely in both directions, with each lug on each member bearing transversely against both lugs ot'the other member. The lugs, 7, 8 on the point B do not lap each other vertically but are left with a vertical space 11 between them sufiicient to accommodate the integral overlap 6 of the lugs 1, 2 of the base A. Recesses 4c, 5 have rear end defining walls 12 and 13 which receive the ends of the lugs 7 and 8; and the recesses 9 and 10 of the point B have forward defining end walls 12 and 13 which receive the for ward ends of the lugs 1 and 2 of the base, and the side walls 12 and 13 as well as the forward faces of the lugs 1 and 2 are so inclined as to produce a wedging fit between the lugs on the base and the recesses of the point.

In-order to secure the point against displacement upon the base, bolt holes 14 and 15 in the lugs of the base, and 16 and 17 in the lugs of the point, are so located as to come into alignment transversely of the tooth when the members are in assembly;

and bolts 18, 19 pass transversely through these holes and draw the lugs firmly into lateral seating. Inasmuch as the bolts 18,

' 19 are sufficiently near parallelism to act substantially in the same direction and are remote from the longitudinal axis of the tooth, and notwithstanding the parts fit snugly together in a manner to prevent rotation as well as tipping of one part upon the other, these bolts by their action develop a turning moment between the two members sutiicient to draw the lugs'into seating in opposite transverse directions. Moreover, the beveled seating faces 12 and 13 translate upward and downward tipping stresses into longitudinal stresses which are resisted by the bolts, and thus add to the security afforded by shearing resistance of the bolts to transverse displacement of the lugs.

I claim:

1. An excavating tooth, comprising separately formed point and base members replaceably mounted the one upon the other; the meeting portions of said members being fashioned to produce between them rabbet splices comprising lapping lugs on each member located on opposite sides of both the horizontal and vertical medial longitudinal planes of the member and leaving in each member, upon opposite sides of said planes, vertically and laterally open recesses to receive the lugs of the other member.

2. An excavating tooth, as described in claim 1 in which the recesses of one member have defining walls in position to receive, in abutment, the ends of the lugs of the other member.

3. An excavating tooth, as described in claim 1, in which a lug on one member and the lug which it laps on the other member are provided with aligned openings to receive a transverse securing bolt.

4. An excavating tooth, as described in claim 1, in whichthe lugs upon one member are overlapped in one of said medial longi tudinal planes, and formed integral through the area of such overlapping, and the lugs on the other member are spaced apart through an area suflicient to receive between them the integral overlapped portions of the lugs of the first named member.

5. An excavating tooth, as described in claim 1, in which the lugs upon one member are overlapped in the direction of one medial longitudinal plane and formed integral through the area of such overlapping; the lugs on the other member are spaced apart through an area su'l'licient to receive between them the integral overlapped portions of the lugs of the first named member; and the lugs on each member are provided with transverse openings which enter into alignment in the assembly of the members, andsecuring bolts extend transversely through the lapped lugs of the assembled members in longitudinal planes of the tooth materially oilset from the said integral area and draw I the lapped lugs laterally together.

6. An excavating toot-h, as described in claim 1, in which the two recesses 011 one member are adapted to receive either lug of the other member, whereby the point is made reversible on the base.

Signed at Chicago Heights, Illinois, 12th day of September, 1927.

ADOLF r. WIKSTROM.

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